Sensory systems use adaptation in order to adjust processing of information to fit the environmental conditions. Understanding adaptation can provide insight into the importance of specific features of sensory stimuli and the efficiency of sensory processing. The auditory system computes interaural time delays in order to localize sound in the azimuthal plane. In the chick the nucleus magnocellularis (NM) is the first central nucleus in the pathway and contains neurons that are highly specialized for faithful transmission of temporal information. While we know a lot about the connectivity and properties of the ITD circuit, little is known about the dynamic changes in processing that occur here. The overall goal of my project is to describe the dynamic changes in the processing of the auditory information that occur in the avian cochlear nucleus. My first aim will describe the nature of adaptation in NM using in vitro electrophysiological techniques. The second aim will untangle the mechanisms that underlie adaptation in NM using a combination of electrophysiological and pharmacological techniques. In the third aim I will examine the role of adaptation in the processing of ITDs using a combination of in vitro electrophysiology and modeling techniques. Relevance: Many communication disorders arise from the malfunctions in the early auditory pathway. Understanding the details of auditory processing at these early stages can assist in devising functional solutions for treatment. Specifically, understanding how the properties of early auditory pathway are adjusted to fit the processing needs can provide insights into the importance of relative features of the sound stimulus and the efficiency of auditory processing.